New house, LOTS of buzzing...

[Marc D. Shunk]

Since the isolation transformer didn't help, you can totally eliminate the voltage SOURCE. Since you have no foreign connections (phone, catv, lan) you can eliminate ground loops and the like between the grounds of these various systems. You say you tried pluggin up all your 3-prong equipment without a ground pin (using 3-prong adapters), so the so-called "noisy ground" is out. You're down to EMI or RFI, in my estimation. You have any dimmer switches nearby? You have any compact fluorescent lamps nearby?

Have you tried switching off every single circuit in the panel except the one you have your crap plugged into? If that helps, switch them back on one by one and see if you can get an offensive "leaky" circuit or circuits pinned down.

[Mark Fiske]

Thanks, Marc. I did try shutting off all the circuits once, and no luck. EMI and RFI are bad news, if that's the case. How do I fix THAT?

Here's something that might interest/ perplex you: the isolation transformer ITSELF started audibly humming AND physically vibrating when plugged into that outlet. Does that tell you anything?

[Mark Fiske]

TODAY, the weather turned from freezing (20-30 degrees F), to just ABOVE freezing and rainy. When I went upstairs to use the guitar, there was no buzzing. I played for awhile, then rain some errands, and when I returned, so had the buzzing.

On a whim, I asked my wife to pour some water on the grounding rod, and 10 seconds later, the buzzing stopped again.

I have NO idea what the length of my grounding rod is, but is 8 ft. the current standard? I suspect that mine is quite a bit less than that, since I can actually wiggle it around in its hole.

Yeah, I know...no dirty jokes.

[Wayne B. Wilson]

Just a thought did you check the neutral for voltage? it may be what is called stray voltage coming from the street. it sometimes happens on high rise bldg s.

[Mark Fiske]

Well, I am going to wait until the buzzing comes back, and then try pouring more water on the grounding rod. I am wondering if the earth AROUND the rod has eroded to the point that there is a "sleeve" of air all the way around it.

Again, is 8 ft. the standard length for a grounding rod? Thats all ANY of the area home improvement stores carry. Suppose a grounding rod change is in order, and that it might fix my problem?

[Wendell F. Cook]

8 ft. is the standard, but I have seen contractors cut them off because they couldn't get them in the ground properly. I'd double check it!

[Bruce A. King]

If all else fails, the power company will probably send someone out with some test equipment at no charge. If you end up suspecting interference, the FCC will send out an investigator too.

[canderson]

You may be picking up EMI interference from the incoming AC. I can tell when my nieghbors furnace is running as my incoming HV power tranformer is downstream from my nieghbors. I agree with Bruce. You should have it investigated by the utility first. Your ground should be 25 ohms or less. You could have a high resistance ground, improper bonding, or a problem with the power co transformer. Good Luck.

[Thomas G. Valosin]

Have you, or a near- by neighbor, recently put a new Plasma TV into service? Some of those devices are capable of generating an unbelievable quantity of RFI (EMF) over a very wide frequency spectrum? Along a similar line - Has a broadband over powerline (BPL) internet access recently been installed?

[Jon Neff]

Mark,

A loose ground or neutral will cause this problem in computer equipment (and presumably sound equipment), the ole "60 hertz hum"...

Do a visual inspection of the main gounding system for your service. In most instances this will be located outside around the meter can. A #4 gauge solid copper wire is typcally connected between the meter can and one or two ground rods driven at least 6 feet apart. If your grounding system is configured like this then:

1. Is the ground wire bare or in conduit?

2. Is the wire corroded where it enters the box or clamps?

3. Is there one or two ground rods? (Some localities in Florida require 2 ground rods due to poor conductivity in sand.)

If you do suspect a bad ground (or neutral) connection, have a licensed electrician check your ground and tighten all hot and neutral wire lugs in the meter and main panel.

Let us know what you find out...

Jon